Chicken with a cold

Hi. I am a new member to Back Yard Chickens. One of my chickens has a cold. Her beak is snotty and her feathers under the wing quite crusty , because of sleeping with her head under her wing, I guess. Will the cold go without a visit to the vet? Is there anything we can do to help her along? And should we wash her crusty feathers or will that make matters worse?
Aside from that she is in wonderful condition and seems quite happy. Good appetite, drinking etc.
She is POL and hasn't laid her first egg yet so quite young.
Thanks for any advise out there.